Dual cycle intercooled engine architectures

Abstract

A gas turbine engine includes a primary gas path having, in fluid series communication: a primary air inlet, a compressor fluidly connected to the primary air inlet, a combustor fluidly connected to an outlet of the compressor, and a turbine fluidly connected to an outlet of the combustor. The turbine is operatively connected to the compressor to drive the compressor. A turbine cooling air conduit extends from an air inlet of the turbine cooling air conduit to an air outlet of the turbine cooling air conduit.

1 . A gas turbine engine, comprising:
 a primary gas path having, in fluid series communication: a primary air inlet, a compressor fluidly connected to the primary air inlet, a combustor fluidly connected to an outlet of the compressor, and a turbine fluidly connected to an outlet of the combustor, the turbine operatively connected to the compressor to drive the compressor; and   a turbine cooling air conduit extending from an air inlet of the turbine cooling air conduit to an air outlet of the turbine cooling air conduit,
 the upstream air inlet connected in fluid communication with the primary gas path at a location downstream of the compressor and upstream of a combustion chamber of the combustor, 
 the air outlet connected to a turbine section for cooling in the turbine section using air from the compressor conveyed through the turbine cooling air path; 
   wherein the turbine cooling air conduit is defined in part by an air conduit of a heat exchanger, the heat exchanger having a fluid conduit in fluid isolation from the air conduit and in thermal communication with the air conduit, the fluid conduit extending from a hydrogen inlet of the fluid conduit to a hydrogen outlet of the fluid conduit, the hydrogen inlet being fluidly connected to a source of hydrogen, the hydrogen outlet being fluidly connected to the combustor via a hydrogen conduit; and   a hydrogen meter in the hydrogen conduit upstream of the combustor for controlling flow of hydrogen to the combustor based at least in part by one of:
 an input for a command power; 
 an input from at least one of a gearbox, a hydrogen expansion turbine, and/or the turbine section; 
 an input from compressor pressure; and 
 an input from a gaseous hydrogen accumulator downstream pressure. 
   
     
     
         2 . The gas turbine engine of  claim 1 , comprising a compressor section fluidly connected to the primary air inlet and having a plurality of compressor stages, and the turbine section fluidly connected to the outlet of the combustor and operatively connected to the compressor section to drive the compressor section, the turbine section having a plurality of turbine stages, and wherein:
 the compressor is a compressor stage of the plurality of compressor stages,   the turbine is a turbine stage of the plurality of turbine stages, and   the air inlet of the turbine cooling air conduit is fluidly downstream of at least one compressor stage of the plurality of compressor stages.   
     
     
         3 . The engine of  claim 2 , wherein the air inlet of the turbine cooling air conduit is fluidly downstream of all compressor stages of the plurality of compressor stages. 
     
     
         4 . The engine of  claim 3 , wherein the air outlet of the turbine cooling air path is fluidly upstream of all turbine stages of the plurality of turbine stages. 
     
     
         5 . The engine of  claim 2 , wherein:
 the heat exchanger is a downstream heat exchanger and the primary gas path is defined in part by an air conduit of an upstream heat exchanger at a location in the primary gas path that is between adjacent compressor stages of the plurality of compressor stages, the upstream heat exchanger having a fluid conduit in fluid isolation from the air conduit of the upstream heat exchanger and in thermal communication with the air conduit of the upstream heat exchanger; and   the fluid conduit of the downstream heat exchanger is fluidly connected to the source of hydrogen via the fluid conduit of the upstream heat exchanger.   
     
     
         6 . The engine of  claim 5 , wherein the combustor is fluidly connected to the source of hydrogen via the hydrogen conduit defined in part by the fluid conduits of the upstream and downstream heat exchangers and by a pump operable to move hydrogen from the source of hydrogen to the combustor. 
     
     
         7 . The engine of  claim 6 , wherein:
 the source of hydrogen is a source of liquid hydrogen operable to provide a supply of liquid hydrogen to the fluid conduit of the upstream heat exchanger; and   the pump is a liquid hydrogen pump disposed in the hydrogen conduit at a location that is fluidly upstream of the fluid conduit of the upstream heat exchanger.   
     
     
         8 . The engine of  claim 7 , wherein the upstream and downstream heat exchangers and the liquid hydrogen pump are sized to convert a majority of the supply of liquid hydrogen into a supply of gaseous hydrogen. 
     
     
         9 . The engine of  claim 7 , wherein the upstream and downstream heat exchangers and the liquid hydrogen pump are sized to convert 90%-100% of the supply of liquid hydrogen into a supply of gaseous hydrogen, by volume. 
     
     
         10 . The engine of  claim 7 , wherein the hydrogen conduit is defined in part by the hydrogen expansion turbine at a location in the hydrogen conduit that is fluidly downstream of the fluid conduits of the upstream and downstream heat exchangers. 
     
     
         11 . The engine of  claim 10 , wherein a hydrogen conduit is defined in part by the gaseous hydrogen accumulator at a location in the hydrogen conduit that is fluidly downstream of the fluid conduits of the upstream and downstream heat exchangers. 
     
     
         12 . The engine of  claim 11 , wherein the gaseous hydrogen accumulator is fluidly downstream of the hydrogen expansion turbine in the hydrogen conduit. 
     
     
         13 . The engine of  claim 10 , wherein the hydrogen expansion turbine is operatively connected to a rotatable component of the gas turbine engine to drive the rotatable component. 
     
     
         14 . The engine of  claim 13 , wherein the rotatable component of the gas turbine engine includes: an output shaft and the gearbox. 
     
     
         15 . The engine of  claim 14 , wherein a rotatable component of the hydrogen expansion turbine is operatively connected to the output shaft through the gearbox to drive the output shaft in parallel with the turbine section, wherein the gear box is operatively connected to a main shaft driven by the turbine section, wherein the main shaft is driven by combined power from the turbine section and the hydrogen expansion turbine. 
     
     
         16 . A method of operating the engine of  claim 1  in an aircraft, comprising:
 heating a flow of gaseous hydrogen in an upstream heat exchanger with compressor air; 
 passing the flow of gaseous hydrogen to a downstream heat exchanger, downstream of the upstream heat exchanger; 
 extracting kinetic energy from the flow of gaseous hydrogen from the downstream heat exchanger to rotate a rotatable component of the aircraft; 
 after the extracting, 
 metering the flow of gaseous hydrogen to the combustor, wherein metering includes:
 receiving input for a command power; 
 receiving input from at least one of a gearbox, a hydrogen expansion turbine, and/or a turbine section; 
 receiving input from compressor pressure; 
 receiving input from the gaseous hydrogen accumulator downstream pressure; and 
 adjusting the flow of gaseous hydrogen in the hydrogen meter to achieve the command power based on at least one of: the input for the command power, the input from the at least one of the gearbox, the hydrogen expansion turbine, and/or the turbine section, the input from the compressor pressure, and/or the input from the gaseous hydrogen accumulator downstream pressure; 
 
 combusting the flow of gaseous hydrogen with the compressor discharge air in the combustor of the gas turbine engine of the aircraft; and 
 cooling the turbine section of the gas turbine engine with air from the downstream heat exchanger. 
 
     
     
         17 . The method as recited in  claim 16 , further comprising:
 expanding a flow of liquid hydrogen to a flow of gaseous hydrogen in the upstream heat exchanger upstream of the downstream heat exchanger relative to hydrogen flow;   compressing cooled air from the upstream heat exchanger;   wherein expanding the liquid hydrogen to gaseous hydrogen includes cooling the compressed air from a first compressor stage; and   supplying heat to the downstream heat exchanger with compressed air from a second compressor stage.   
     
     
         18 . The method of  claim 17 , further comprising, using rotation of the rotatable component, generating one or both of: thrust, and electrical power. 
     
     
         19 . A gas turbine engine of an aircraft, comprising:
 a primary gas path having means for fluidly communicating in series a primary air inlet, a compressor, a combustor, and a turbine, the turbine operatively connected to the compressor to drive the compressor; and   a turbine cooling air conduit extending from an air inlet of the turbine cooling air conduit to an air outlet of the turbine cooling air conduit,   means for connecting the primary gas path to the combustor at a location downstream of the compressor and upstream of a combustion chamber of the combustor,   means for cooling in the turbine section using air from the compressor conveyed through the turbine cooling air path;   wherein the turbine cooling air conduit is defined in part by an air conduit of a heat exchanger, the heat exchanger having a fluid conduit in fluid isolation from the air conduit and in thermal communication with the air conduit, the fluid conduit extending from a hydrogen inlet of the fluid conduit to a hydrogen outlet of the fluid conduit, hydrogen inlet being fluidly connected to a source of hydrogen, the hydrogen outlet being fluidly connected to the combustor;   a hydrogen conduit; and   a hydrogen meter in the hydrogen conduit upstream of the combustor for controlling flow of hydrogen to the combustor based at least in part by one of:
 an input for a command power; 
 an input from at least one of a gearbox, a hydrogen expansion turbine, and/or the turbine section; 
 an input from compressor pressure; and 
 an input from the gaseous hydrogen accumulator downstream pressure.